Encode32 vs Encode64

I am looking at the code now, specifically LZ4n project, and I am trying to understand why you have 32 and 64 versions.
And a quick scan didn't show anything there that is hard coded for specific bitness.

Oh, that is great. I am focusing on 64 bits only, and if it can run (even somewhat inefficiently) on 32 bits, this is great.

Now, I have a pretty strange need. I need to be able to compress data is isn't sitting on the same memory position.
For example
var first = malloc(4096*12);
var second = malloc(4096 * 16);
var third = malloc(4096 * 8);

And now I need to compress all three buffers (which compose a single logical value), but aren't following one another in memory.
Any suggestions on how to do that?

Current, I have to copy them into a single long buffer, but I would really like to avoid having to do that.